The present invention relates to a driving tool for fasteners including locking means.
German Petty Patent 88 10 753 discloses a driving tool including locking means, wherein a trigger lever has a longitudinally extending recess opening towards an actuating member so that the actuating member may not be readily actuated by the trigger lever. Said recess receives a movably mounted slide member which is operatively connected to a sensor. In response to actuation of the sensor the slide is displaced within the trigger lever so as to be located below said actuating member. When the actuating member is in this position, actuation of the trigger lever results in a displacement of the actuating member. Furthermore the operative connection between the sensor and the slide member is such that the trigger member even if the sensor has been placed upon a workpiece may be returned to its rest position so as to be actuated for triggering a further drive-in operation. Such means for individual triggering is provided in relatively big driving tools or in driving tools for fasteners of substantial length (e.g. 130 mm). Actuation of the trigger lever triggers only a single drive-in operation as opposed to driving tools of the repetition type wherein driving-in of fasteners occurs sequentially at a constant frequency as long as the trigger lever remains actuated. When the sensor is returned to its rest position with the trigger lever having been actuated, the sensor cannot be lifted again because the slide member will abut the actuating member. This is why the operator will have to release the trigger lever in order to retrigger a drive-in operation.
U.S. Pat. No. 4,629,106 discloses a driving tool including locking means, wherein the trigger lever receives a resiliently biased actuating lever pivotally mounted to co-operate with a latch lever also pivotally mounted within the trigger lever, with the latch lever being actuated by the sensor. In this driving tool when the sensor has been actuated individual triggering is not possible without causing the sensor to return to its rest position.
German patent application 30 21 884 discloses a driving tool including a sensor having a resilient telescopic section arranged to cooperate with a lever pivotally mounted in the trigger lever so that said lever remains in its rest position if the trigger lever is actuated first and the sensor is actuated thereafter. Triggering of the drive-in operation, accordingly, may be achieved only in a reverse sequence. Furthermore, in this driving tool individual triggering is possible by means of the trigger lever even when the sensor has been actuated. If the sensor is moved to its rest position with the trigger lever having been actuated, triggering of a drive-in operation by placing the sensor upon the workpiece and releasing and reactuating the trigger lever is not possible.
German patent specification 23 11 147 discloses a driving tool including a uniquely shaped lever pivotally mounted on a trigger member. This lever is caused to pivot by the sensor when the sensor is moved into its operative position. A pin is connected to the hollow trigger member and is arranged to actuate said lever only when said lever had been pivoted by the sensor first. A reverse sequence of operation is not possible. In this driving tool sequential individual triggering operations are possible when the sensor has been actuated. If the sensor when the trigger lever has been actuated is moved to a position close to its rest position, further individual triggering in a reverse sequence of operation is no longer possible.